This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Observational Study to Assess the Frequency of Lidocaine Ineffectiveness in Hard-to-treat ADHD (NCT04167189), a na early/phase 1 study. The primary outcome is Observational Study: Number of Participants With Lidocaine Ineffectiveness by Taste Test in Hard-to-treat ADHD.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04167189 |
| Phase | EARLY/Phase 1 |
| Condition | ADHD |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 28 |
| Arms in the primary outcome | n/a |
| Lead sponsor | PhenoSolve, LLC |
| Results posted | Yes |
2. Clinical Question
Population
The stated population is people with hard-to-treat ADHD. The registry record does not report detailed eligibility criteria or describe the participants’ demographic or clinical characteristics. Enrollment is listed as 28, but the record does not say how many participants completed testing or contributed to the primary outcome.
Intervention
Participants were to be tested with lidocaine gel. The registry describes the procedure as asking participants to identify each taste and its intensity. Details such as the amount of gel, administration procedure, and criteria for classifying a response as ineffective are not reported in the registry record.
Comparator
This is a single-group observational study, not a randomized comparison. The record refers to a comparison with previously published studies in pediatric populations, but those studies are not a concurrent control group. The registry record does not describe a like-for-like control arm within this study.
Primary question
The study asks how frequently lidocaine is ineffective in people with hard-to-treat ADHD, as assessed by a taste test. The planned primary measure is the number of participants classified as having lidocaine ineffectiveness. The registry record does not report the observed count, a prevalence estimate, or the rule used to determine ineffectiveness. The question is therefore identifiable from the study description, but its answer cannot be read from the recorded outcome results.
3. Trial Design
The registry describes an observational, single-group study of lidocaine ineffectiveness in hard-to-treat ADHD. Allocation is listed as not applicable, and masking is listed as none. These features mean the record does not describe a randomized treatment assignment or a blinded comparison. It lists lidocaine gel as the intervention and says participants would be tested with it.
The study is marked completed, with enrollment listed as 28. The registry also labels the phase as EARLY PHASE1. That label does not change the stated observational, single-group structure, and the record does not provide further explanation of how the phase designation relates to the study’s aims.
The primary outcome is described as a count of participants with lidocaine ineffectiveness by taste test. The stated timeframe is on the day of testing, with approximately 30 minutes for the clinic visit. The study description says participants would identify each taste and its intensity. Further details about the test procedure, participant flow, recruitment, eligibility, or how the outcome was classified are not reported in the registry record.
The registry refers to previously published studies in pediatric populations as a comparison context. Those studies are not described as a concurrent arm, and the record does not establish that their populations or methods are directly comparable. The record lists one outcome measure and no analyses. It does not report a primary outcome estimate or a statistical comparison with the historical studies.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Hard-to-treat ADHD |
|---|---|
| STARTED | 28 |
| COMPLETED | 28 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Study population vs. previously published studies in pediatric populations (Nakai et al, 2000)
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Subjects who completed the study
| Characteristic | Unit | Hard-to-treat ADHD |
|---|---|---|
| Participants analysed | 28 | |
| Age, Continuous | years | 16 (SD 7.0) |
| Sex: Female, Male: Female | Participants | 7 |
| Sex: Female, Male: Male | Participants | 21 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 3 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 25 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 22 |
| Race (NIH/OMB): More than one race | Participants | 6 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 28 |
| Hard-to-treat ADHD (does not respond to available ADHD drugs) | Participants | 28 |
6. Primary Endpoint
The registry lists the primary outcome as Observational Study: Number of Participants With Lidocaine Ineffectiveness by Taste Test in Hard-to-treat ADHD, measured over on day of testing, approximately 30 minutes for clinic visit.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants classified as having lidocaine ineffectiveness by taste test. It is a binary participant-level outcome summarized as a count: each participant would be classified according to whether the test indicated ineffectiveness, and the endpoint would count participants in that category. The registry description says participants would identify each taste and its intensity.
This kind of endpoint is relevant to the stated question because the study aims to assess how frequently ineffectiveness occurs in the specified population. A count can describe how many participants met the study’s classification rule. To interpret the frequency as a prevalence estimate, readers would also need a clearly defined denominator and an operational definition of ineffectiveness. The record lists enrollment as 28 but does not report the number assessed for the endpoint, the observed count, or the classification threshold.
The timeframe is the day of testing, with approximately 30 minutes for the clinic visit. The registry does not report a longer follow-up period or repeated outcome assessments. The endpoint’s intended meaning is clear at a broad level, but details of test administration, scoring, and classification are not reported in the registry record. Without the observed result and these details, the endpoint definition cannot be independently applied or its estimate interpreted in detail.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a completed study with enrollment of 28 and a planned primary measure: the number of participants with lidocaine ineffectiveness by taste test. It does not report the observed primary outcome count, an estimate of prevalence, uncertainty around an estimate, or an analysis. Consequently, the central question—how often ineffectiveness was identified in the study population—has no result reported in the registry record.
Enrollment is not itself an outcome. The listed enrollment of 28 does not establish that all enrolled participants completed the taste test, had evaluable results, or were included in an analysis. The record does not give participant flow or an endpoint denominator. It is therefore not possible to infer a proportion from enrollment or to assess how representative the tested participants were of the stated population.
The design also limits what a result could establish. This is described as an observational, single-group study, with allocation not applicable and no masking. There is no concurrent control group in the registry record. Its reference to previously published pediatric studies does not make those studies equivalent to a control arm. Differences in populations, test procedures, and outcome definitions could affect comparisons, and comparability is not established in the record.
The absence of an analysis means that no inferential claim can be evaluated from the registry results. The record does not report a confidence interval, hypothesis test, or model-based estimate for the primary endpoint. In general, a confidence interval communicates the range of values reasonably compatible with data under the assumptions of the analysis; without a reported estimate and interval, the precision of the study’s primary result cannot be assessed.
There is a separate safety record: for the hard-to-treat ADHD group, 28 participants are listed at risk for serious adverse events and 0 as affected; the corresponding figures for other adverse events are 28 at risk and 0 affected, with 0 deaths. These are registry safety counts, not the primary efficacy or prevalence outcome. They should not be substituted for the missing taste-test result.
Any sample-size calculations associated with the statistical presentation are planning illustrations, not evidence of observed power and not a description of this study’s original design. The record does not report the trial’s own sample-size justification. Overall, the registry supports a description of the question and design, but not a numerical conclusion about the frequency of lidocaine ineffectiveness.
9. Statistical Methods Explained
What does a participant count mean?
The primary measure is a count of participants classified as having lidocaine ineffectiveness. In general, a binary outcome assigns each assessed participant to one of two categories, such as meeting or not meeting a prespecified criterion. A count reports the number in one category. To turn that count into a prevalence estimate, the denominator must also be specified: it should be clear which participants were assessed and which had usable results.
The registry record lists enrollment as 28, but it does not report the number who completed the test or contributed to the endpoint. It also does not provide the outcome count. The test is described as asking participants to identify each taste and its intensity, but the operational rule for deciding that lidocaine was ineffective is not reported in the registry record. A count cannot be interpreted fully without knowing both how the classification was made and which participants were included.
How should uncertainty be understood?
In general, a point estimate summarizes the observed data, while a confidence interval conveys uncertainty around that estimate under a statistical model and its assumptions. For a prevalence outcome, uncertainty depends on the observed count and the denominator, among other assumptions. A confidence interval does not show the range of individual participants’ responses; it expresses uncertainty about the population quantity being estimated.
No primary outcome estimate or confidence interval is reported in the registry record. Therefore, there is no posted numerical result whose precision can be evaluated. It is not possible to determine whether a possible estimate would be precise or imprecise from enrollment alone. In particular, enrollment cannot replace the missing endpoint denominator or observed count.
What is the role of a comparison?
The study is identified as observational and single-group, with allocation listed as not applicable. It does not describe random assignment to different conditions or a concurrent control group. The registry’s mention of previously published studies in pediatric populations is a historical comparison context, not an internal control arm. In general, comparisons across separate studies can be affected by differences in participant selection, procedures, measurement rules, and study setting. The record does not report a statistical analysis that accounts for such differences or a direct comparison with those studies.
Masking is listed as none. In general, masking can reduce the influence of knowledge about a study condition on measurement or assessment, depending on the design. The record does not explain whether or how the absence of masking might have affected the taste-test classification. The test and its classification criteria are not described in enough detail to assess that issue.
What do the planning calculations represent?
General sample-size calculations can illustrate how many participants might be needed under chosen assumptions to detect a specified effect with a chosen statistical procedure. They are planning tools, not observed results. The stated illustration assumptions include a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Those assumptions do not describe the registry’s single-group observational design. The record does not report that these were the study’s original design assumptions or provide a sample-size justification for the trial.
Any displayed sample-size values should therefore be read as planning illustrations tied to their stated assumptions, not as evidence that the study had a particular probability of finding a result. In particular, sample-size calculations are not observed power. Because the registry record does not report the primary outcome estimate, readers also lack the observed effect information needed to interpret an illustration based on an observed effect. The calculations should not be treated as an analysis of participants in this study.
What can be concluded from the registered analysis information?
The record lists one outcome measure and 0 analyses. This indicates that the primary measure is named, while no analysis results are reported in the record. It does not establish whether analyses were conducted outside the registry or whether findings were reported elsewhere. Those details are not reported in the registry record. A statistical method, such as a test, interval procedure, adjustment, or model, cannot be attributed to this study on the basis of the registered information.
In general, analysis choices should match the outcome, study design, and question. A count and an estimated prevalence require clear reporting of the assessed population, outcome rule, and denominator. If a comparison is made with historical studies, the basis for comparability and the method used to account for differences should also be explained. Those analysis details and results are not reported in the registry record, so a reanalysis or independent verification of the primary finding is not possible from the registered information.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure and 0 analyses. It identifies the primary measure as a count of participants with lidocaine ineffectiveness by taste test, but it does not report an analysis result. A single listed outcome does not by itself establish the full set of outcomes, comparisons, or analyses considered in the study.
Multiplicity concerns arise when multiple outcomes, time points, subgroups, or statistical comparisons are assessed. In general, examining many results can increase the chance that some appear notable by chance, so analysis plans sometimes specify how such testing will be handled. The registry record does not report a multiplicity strategy, a prespecified testing hierarchy, or whether additional analyses were planned. It also does not report interim analyses.
Missing-data handling is likewise not reported in the registry record. Although enrollment is 28, the record does not state how many participants completed the taste test, whether any measurements were missing or unusable, or how missing results would be handled. It does not describe exclusions, imputation, or sensitivity analyses. Without participant flow and a defined endpoint denominator, the analysis population cannot be established.
The record does not report whether the primary analysis included all enrolled participants, only those tested, or another defined group. It also does not give a statistical analysis plan or explain how participants were classified if their test responses were incomplete or ambiguous. These gaps mean that the population represented by the primary endpoint and the robustness of any estimate cannot be assessed from the registry record. No outcome estimate or analysis is available to determine whether multiplicity or missingness affected the reported findings.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Hard-to-treat ADHD | 0 | 28 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Hard-to-treat ADHD | 0 of 28 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Hard-to-treat ADHD | 0 of 28 |
For the hard-to-treat ADHD group, the registry lists 28 participants at risk for serious adverse events and 0 participants affected. For other adverse events, it lists 28 at risk and 0 affected. Deaths are listed as 0. The record does not list serious adverse event terms.
These figures are safety counts. They are distinct from the primary taste-test endpoint, which concerns lidocaine ineffectiveness. The listed at-risk counts should not be read as proof that all 28 participants completed the primary assessment, because the safety and outcome records do not establish the same analysis denominator.
In general, a recorded zero means that no event was entered in that category for the stated reporting group; it does not establish that an event was impossible or that no event occurred outside the recorded information. The registry record does not provide further detail about adverse-event collection, observation duration, severity definitions, or completeness of reporting. The safety counts should therefore be interpreted as the registry’s recorded figures, not as a comprehensive assessment of risk.
12. What the Result Does, and Does Not, Mean
The study’s stated purpose is to assess the frequency of lidocaine ineffectiveness in hard-to-treat ADHD using a taste test. The registry record describes the endpoint and the planned assessment in broad terms, but it does not report the primary outcome count or a prevalence estimate. The central numerical question therefore remains unanswered in the registry record.
The absence of an outcome result is not evidence that ineffectiveness was absent, common, or uncommon. It also does not establish whether the test was successful in distinguishing participants’ responses. Without the observed count, denominator, and outcome classification rule, no estimate can be reconstructed from the listed enrollment.
Even if a prevalence result were available, its interpretation would depend on how the participants were selected and assessed, how ineffectiveness was defined, and how completely the endpoint was measured. The registry does not report detailed eligibility criteria, participant characteristics, test procedures, or missing-data handling. Those omissions make it difficult to judge the reach of any result beyond the participants who were assessed.
The observational, single-group design also does not support a randomized treatment comparison. The historical comparison mentioned in the record is not a concurrent control group, and the registry does not report an analysis establishing comparability with the previously published pediatric studies. The record therefore cannot support a causal conclusion about treatment effects or a direct claim that this study’s population differs from another study population.
The safety record lists 0 serious adverse events, 0 other adverse events, and 0 deaths among a group with 28 listed at risk. Those entries describe the registry’s safety reporting; they do not answer the primary prevalence question and should not be taken as a complete assessment of safety beyond the recorded information.
13. Why This Trial Matters Statistically
This study illustrates a basic distinction between a clearly stated research question and a reported result. The registry names a specific population, a taste-test assessment, and a count-based primary outcome. Yet it lists 0 analyses and does not report the primary outcome count. A study description can therefore identify what investigators intended to measure without showing what the measurement found.
It also highlights why an outcome definition matters. A count of participants classified as having ineffectiveness is interpretable only when readers know the classification rule and the participants who formed the denominator. The record describes identification of each taste and its intensity, but not the threshold or scoring rule. This limits reproducibility and makes it difficult to compare the intended measure with outcomes from other studies.
The design makes careful language about comparison important. An observational single-group study can describe results in the assessed participants, but a reference to previously published studies does not create a concurrent control group. Comparing study results requires attention to differences in populations and measurement. The registry record does not report an analysis addressing those issues.
Finally, the record separates planned measurement from statistical evidence. Planning calculations can illustrate assumptions, but they do not replace observed results or indicate observed power. Here, the trial’s original sample-size justification is not reported in the registry record, and the primary analysis is not reported. For clinical researchers and biostatisticians, the practical lesson is to look for a complete chain of reporting: a reproducible endpoint definition, an explicit analysis population, the observed count and denominator, and an account of uncertainty. Those elements are not available for the primary endpoint in this record.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The most important limitation for interpreting this study record is that the primary outcome result is not reported in the registry record. No observed count, prevalence estimate, confidence interval, or analysis is listed. The registry reports enrollment of 28, but not how many participants were tested or included in an outcome denominator.
The endpoint description is incomplete for reproducibility. Participants were to identify each taste and its intensity, but the record does not state the specific rule for classifying lidocaine as ineffective. It also does not describe detailed test procedures, how ambiguous responses were handled, or whether the outcome was assessed consistently across participants.
The study is observational and single-group, with allocation not applicable and masking listed as none. It does not include a concurrent control group. The historical pediatric studies cited as a comparison context may differ in population or methods, and the registry does not report a direct analysis establishing comparability. The record also does not provide detailed eligibility criteria or participant characteristics, limiting assessment of how well the enrolled group represents the broader stated population.
Participant flow, missing-data procedures, analysis populations, multiplicity handling, and the statistical analysis plan are not reported in the registry record. The record does not report the trial’s own sample-size justification. While safety counts are listed, details of adverse-event collection and observation are not reported. Together, these limitations mean that the registered information supports a description of the study’s intent and broad design, but not a detailed appraisal of its primary result or precision.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Observational Study to Assess the Frequency of Lidocaine Ineffectiveness in Hard-to-treat ADHD — NCT04167189.
- Registry record last updated 2021-07-02; status last verified 2021-06.
- Results first posted 2021-07-02.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry describes a completed observational, single-group study of lidocaine ineffectiveness in hard-to-treat ADHD. Enrollment is listed as 28, and the planned primary endpoint is the number of participants classified as having ineffectiveness by taste test. Participants were to identify each taste and its intensity after testing with lidocaine gel.
The registry record does not report the primary outcome count, an estimate, or an analysis. It does not report the endpoint classification rule, participant flow, or analysis population. Safety figures list 28 at risk and 0 affected for serious adverse events, 28 at risk and 0 affected for other adverse events, and 0 deaths. These are safety counts and do not answer the primary outcome question.